Commits
Miklos Szeredi authored and Greg Kroah-Hartman committed cb8e5c9cd03
splice: fix misuse of SPLICE_F_NONBLOCK commit 6965031d331a642e31278fa1b5bd47f372ffdd5d upstream. SPLICE_F_NONBLOCK is clearly documented to only affect blocking on the pipe. In __generic_file_splice_read(), however, it causes an EAGAIN if the page is currently being read. This makes it impossible to write an application that only wants failure if the pipe is full. For example if the same process is handling both ends of a pipe and isn't otherwise able to determine whether a splice to the pipe will fill it or not. We could make the read non-blocking on O_NONBLOCK or some other splice flag, but for now this is the simplest fix. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Jens Axboe <jaxboe@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>